We present an approach to the design of mixed reality spaces that aims to create a more harmonized and unified user experience. We refer to these as blended spaces. Blended spaces draw upon a description of physical and digital spaces in terms of the ontology, topology, volatility and agency. By describing physical and digital spaces in these terms we are able to use the process and design principles of conceptual blending to arrive at a design that maximizes the relationships between the spaces. It also guides the development of the touch points between the physical and digital spaces. We discuss the user experience in blended spaces and briefly allude to the significant philosophical implications that blended spaces of the future will have to deal with.

Novel speech systems such as the conversational agents being developed by the Companions Project (www.companions-project.org) can be simulated using the Wizard of Oz methodology. In this approach technologies that are not yet ready for testing by people are replaced by a human, both for prototyping and collecting additional dialogue data. In the case of Companions we want to observe what it would be like for people interact with a fully functional embodied conversational agent (ECA) and to collect samples of typical dialogue in order to explore, evaluate and model dialogue strategies. One controversial aspect of the Wizard of Oz approach is whether people should be aware that they are interacting with a simulation or whether they should be "fooled" into thinking they are interacting with a real system. Clearly there are ethical issues involved in fooling people, but some argue that unless the participant believes the simulation to be real, the results of any experimentation will not be applicable to the real situation. Over the course of several previous Wizard of Oz experiments our observations suggest that the dialogues produced do not significantly differ whether the participants know that the technology is faked or not. This hypothesis was investigated by collecting dialogues from two groups of participants. One group of participants believed that the Wizard of Oz speech system was in fact a fully computerised prototype and the other group knew that they would be talking through the interface to a hidden person (the wizard). The dialogues were analysed for differences attributable to the participants' beliefs about the system. This analysis was undertaken by an independent "blind" reviewer, a dialogue expert who attempted to allocate participants to one group or the other. His guess was wrong for four out of the six participants. Thus it appears that whether people believe they are interacting with a real system or not does not effect the dialogues and other factors, for example the personality of the person engaged in a dialogue with an ECA, are more important.

Wizard of Oz experiments allow designers and developers to see the reactions of people as they interact with to-be-developed technologies. At the Centre for Interaction Design at Edinburgh Napier University we are developing a Wizard of Oz system to inform and further the design and development of Companion based technologies. Companions are intelligent, persistent, personalised, multimodal, natural language interfaces to the Internet and resources such as photo or music collections. They have the potential of turning our current human-machine interactions into human-machine relationships. In particular, a Companion prototype for reminiscing about a photo collection, called PhotoPal, is being used in our experiments. Several Wizard of Oz experiments have been run to assess people's reactions and thoughts about using a Companion interface. The feedback from these experiments has informed both the design direction and choice of development technologies going forward. The Wizard of Oz system has also been put to use in a classroom of young pupils and to aid adults make more productive use of the Internet for learning. Further experiments to investigate the appropriateness of Companion dialogue are planned.

Personification technologies are technologies that encourage people to anthropomorphize. These technologies try to get people to form relationships with them rather than simply interact with them. They may do this through having behaviours that encourage people to attribute personality or emotion to them. They may be persuasive technologies in the sense of Fogg that aim to get people to do things they would rather not do. They may promote trust. The convergence of a number of technologies is making personification technologies possible. Speech as an interaction is finally becoming robust and useable and is very influential in people attributing intelligence to devices and systems. Human language technologies allow devices to understand, or appear to understand, conversation. Interactions are becoming more natural and engaging. Avatars appear more congenial and coordinated. Building on the experience of a previous project, and drawing on the experience of a four year multi-disciplinary project, called Companions, the authors are keen to build community relationships around the notion of personification technologies. This includes the design, engineering, research (including ethics and social issues) and usability communities.